


When you need him (Mettaton/Undyne and Undyne/Alphys)

by Belzy_Elzy_Bub



Series: Everyone loves a Good Entertainer [1]
Category: Undertale (Video Game)
Genre: Multi, Smut, Voyeurism, but everyone else is the same age, collection of smut, mettaton does stuff, mostly at least, post-true pacifist ending, request pairings and kinks, very little plot
Language: English
Status: Completed
Published: 2015-10-15
Updated: 2015-10-15
Packaged: 2018-04-26 11:18:04
Rating: Mature
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 1,487
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/5002723
Author URL: https://archiveofourown.org/users/Belzy_Elzy_Bub/pseuds/Belzy_Elzy_Bub
Summary: <blockquote class="userstuff">
              <p>Mettaton is famous for being the robot who could on TV. The one who fought fabulously against a human...However, there is one other thing he is well known for...</p>
            </blockquote>





	When you need him (Mettaton/Undyne and Undyne/Alphys)

**Author's Note:**

> This is just a collection of nsfw stuff with various kinks mettaton either has or just my own guilty pleasure  
> i have a few different stories planned out but feel free to request any other combos or kink fics because im ~~a horny boy with a love for robabes~~ in need of practice
> 
> also; its my headcannon that mettaton has the option to have both sets of genitals... if you are confused just imagine a transformer but instead of a car its a dick (surprise!)

Mettaton was on his way to visit Doctor Alphys. She was sick, he was made to make monsters happy; and good ol' doc was a bit more than just a fan. 

Little did he know that Undyne was over. And he did recall yelling for them to kiss and touch butts while back...The thought slipped his mind. Besides, when Alphys was sick she would just watch anime and write sappy friend-fiction or play those Otome (That is what she called them, right?) games in her dark room. 

Approaching the lab, Mettaton gave a very quick rap at the door; humming his theme song as he waited. And waited. And waited.

The lights were on, so Doctor Alphys must be home. And she's obviously sick, so she wouldn't be doing anything dangerous of attention-draining like an experiment or trial of an invention of hers...But where was the familiar stout girl? Tapping a shiny boot, Mettaton looked around the outside, trying not to look desperate to get it.

The abrupt opening of the front door nearly scared Mettaton to death. Low and behold, it was the lady of the hour, out of breath. "O...O-Oh! Mettaton, I'm surprised t-to see you..." nearly gurgled the lizard monster, a heavy flush on her face. Alphys appeared to either have a fever or a girlfriend. He was hesitant to go in with that kind of reaction, but stepped in anyways. 

As he sat down the bag of goods on a nearby counter, Mettaton gave out a soft chuckle in her direction. "Well, It _is_ my primary function to take care of you, right? Remember the good ol' days, Doctor?" He cooed, rummaging for the cold medicine. 

A low cough caught his attention. It was curt and low, a contrast to the nasal-like voice of Alphys. 

"Excuse me, you oversized hunk of glitter." called the voice that could only belong to the head of the king's guard. Undyne was on the couch, the dim lights and slightly ajar couch cushion under her legs almost a telltale sign that he was interrupting something...saucy. She begrudgingly got off the couch and stood next to Alphys and defensively put an arm on her small shoulder. "But 've got this covered, okay?" she said, nearlying spitting. 

Alphys nearly screamed she looked so embarrassed, much to the amusement of both parties. Before Mettaton had the chance to turn-spin around and leave with style, the scientist clapped her hands together with a loud exclamation. "Undyne! Th-This could be the the solution...t-t...to our... _problem_?" she said, voice trailing off as she shuffled her clawed feet. " the one when i cant satify you because im t-too sick..." she squeaked, almost inaudible. 

The two coldblooded monsters started to discuss by themselves, murmuring and with Undyne arguing and gesturing towards Mettaton once or twice. After a few minutes, Alphys turned back to the idol and smiled. Undyne looked a bit more calm, a slight smirk on her face. 

"Well, lets see how good of an entertainer you actually, _Rectangle_." She said, the tone of her voice much deeper. 

"What are you doing, be care-!!" He started before being shoved back first onto the couch. He landed with a soft grunt and Undyne climbed on top of him; straddling the robot monster. She roughly groped at his chest and began rubbing against him, the grin on her face almost sadistic.

Mettaton had very little objections to what was going on, but he wasn't used to being 'played with' so roughly; what can you expect from someone like Undyne the Undying? She leaned down to start kissing the soft material that made his lips, biting on them with her sharp teeth before sticking her coarse tongue in his mouth. 

The pair had at it for a bit, before Undyne moved down to lick Mettaton's waist. From the start of his sensitive soul compartment, up to his nodules and buttons; all while belittling him. "Disgusting, you think you can impress anyone with a body like this." she murmured in his ear before biting it. 

At that point, Mettaton was a hot mess, hair rough, head cocked to the side and mouth drooling. He was quietly thanking Doctor Alphys for giving his body sensitive nerves and making his body as lifelike as possible. However, it also was terrible with all this teasing. He just wanted to get relief from the hot coils inside him.

"Hey!" snapped Undyne, jerking his chin to look back at her. "Did I say you could you could look away, slut?" she barked, nails digging into his soft metal. 

He gave a half assed grunt in reply before Undyne began to move and stand up while pushing him back into the couch with her foot. Whining softly, Mettaton tried to rub himself with the friction of the couch's fabric, but to no avail. 

Alphys sat and watched, her quiet, sick sniffling mixed in with moans of her own as she began to touch herself and watch her girlfriend top her creation.

Undyne began to strip, removing her boots, shirt and pants. She was left in her underclothes which were quite expected; boxers and a sports bra. She had a very impressive build, noted both Alphys and Mettaton.

She strutted over and mounted Mettaton near his upper chest, nearly crushing him. This won another moan out of Mettaton as she leaned closer, and shoved his face into her abdomen. "Kiss it." she said, nearly breaking the poor robot's neck in the process. He did as he was told, licking and kissing each scar, muscle and inch of skin in sight. Undyne shifted her position to give Mettaton more room and access to her, head rolling back as she took it all in. He began throwing in comments of her beauty, barely making comprehensible sentences at this point. Undyne decided that he has been good enough and to reward Mettaton, running a long finger down his chest and to his groin area. She started to rub circles around his thigh, relishing in the fact of how soft it felt. Mettaton let out more moans as he continued onto Undyne's bicep, breathing becoming erratic. "Haa...Aahh..." he groaned. "Hm...? What's that, pretty boy?" Undyne remarked in a weak tone, her smile growing. Mettaton looked up desperately with expectant eyes. Undyne just laughed. "Oooh no...I want you to beg for it." huskily whispered the fish monster, her half-lidded gaze commanding. 

He bit his lip, trying to hide how horny he felt. The two stared at eachother, flush clearly on their faces. Mettaton's panting the only thing keeping them from an awkward silence. 

"Go on, you slut. I know what you want." she whispered.

Mettaton let out a shaky sigh, face pink. "I...Want you to touch me..." he said, not making eye contact. 

"Hm?"

"I want you...t-to...touch me."

Undyne patted him on the shoulder, making a snarky and sarcastic face. "Done. Happy?"

Mettaton's sexual frustration was more than enough for his own conscious to fly south for the time being. Fixing his position, he opened his mouth again, "I want you to make me come." he breathed.

Undyne finally leaned down and lifted his thighs up, dipping her head down to get a taste of the robot, using her free hand to move the things obstructing her. It was almost not a surprise that the one and only 'MTT' tasted like flippin' Glamburgers. Did Alphys program that or some junk? 

As she ran her tongue around him and started to eat Mettaton out, he arched his back and let out a porn-star worthy moan. He gripped her red hair with one hand, the other tightly clasped onto his mouth; two fingers being bit on in attempts to keep himself quiet.

She continued to lick and run her tongue inside him until he seemed to be very close. Undyne pulled back, making Mettaton whine very loudly. With a smirk on her face as she licked her lips from what of Mettaton's juices was on her and started to remove her boxers. She leaned down and flipped one of the few switches he had exposed to reveal his throbbing erection.

Mettaton felt the weight on him readjust as she mounted him for what was hopefully the last time. With her powerful legs wrapped around his waist, Undyne began to ride Mettaton and let out her own share of lewd noises. 

It wasn't but one minute later when the two came, Alphys close behind as she watched her girlfriend's head get thrown back and let out a glorious moan. Mettaton looked absolutely disheveled, bite marks along his metal plating and face drenched in sticky sweat. Undyne was still panting, the workout satisfactory, and she got off of her temporary partner.

After they all cleaned up, Mettaton ended up giving Alphys the meddicine and they gathered under a single blanket to sleep/snuggle.


End file.
